Larry, Gord VE3HKE used subaudible tones to limit access to the autopatch on VE3TTY. I still have mine! It was a Ferrotronics unit that was adjusted with a pot, definitely not programmable!
I seem to remember that was around 1972/73, not much later because the autopatch went into VE3RPT in 1974 and I know TTY's was on first. We made limited use of CTCSS on VE3RPT at times in the early seventies, but it was for command station access, not general use. 73 Nigel ve3id --- In [email protected], "larry allen" <[EMAIL PROTECTED]> wrote: > > Does anyone know when subaudabe tones were introduced into ham radio > repeaters.. or more specifically when they became standard in ham radio > sets? > Larry ve3fxq >
